Added Inflector#parameterize for easy slug generation ("Donald E. Knuth".parameterize => "donald-e-knuth") #713 [Matt Darby]

Author: David Heinemeier Hansson

activesupport/CHANGELOG

@@ -1,5 +1,7 @@
 *Edge*
 
+* Added Inflector#parameterize for easy slug generation ("Donald E. Knuth".parameterize => "donald-e-knuth") #713 [Matt Darby]
+
 * Changed cache benchmarking to be reported in milliseconds [DHH]
 
 * Fix Ruby's Time marshaling bug in pre-1.9 versions of Ruby: utc instances are now correctly unmarshaled with a utc zone instead of the system local zone [#900 state:resolved] [Luca Guidi, Geoff Buesing]

activesupport/lib/active_support/core_ext/string/inflections.rb

@@ -87,6 +87,25 @@ def demodulize
           Inflector.demodulize(self)
         end
 
+        # Replaces special characters in a string so that it may be used as part of a 'pretty' URL.
+        # 
+        # ==== Examples
+        #
+        #   class Person
+        #     def to_param
+        #       "#{id}-#{name.parameterize}"
+        #     end
+        #   end
+        # 
+        #   @person = Person.find(1)
+        #   # => #<Person id: 1, name: "Donald E. Knuth">
+        # 
+        #   <%= link_to(@person.name, person_path %>
+        #   # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>
+        def parameterize
+          Inflector.parameterize(self)
+        end
+
         # Creates the name of a table like Rails does for models to table names. This method
         # uses the +pluralize+ method on the last word in the string.
         #

activesupport/lib/active_support/inflector.rb

@@ -240,6 +240,25 @@ def humanize(lower_case_and_underscored_word)
     def demodulize(class_name_in_module)
       class_name_in_module.to_s.gsub(/^.*::/, '')
     end
+    
+    # Replaces special characters in a string so that it may be used as part of a 'pretty' URL.
+    # 
+    # ==== Examples
+    #
+    #   class Person
+    #     def to_param
+    #       "#{id}-#{name.parameterize}"
+    #     end
+    #   end
+    # 
+    #   @person = Person.find(1)
+    #   # => #<Person id: 1, name: "Donald E. Knuth">
+    # 
+    #   <%= link_to(@person.name, person_path %>
+    #   # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>
+    def parameterize(string, sep = '-')
+      string.gsub(/[^a-z0-9]+/i, sep).downcase
+    end
 
     # Create the name of a table like Rails does for models to table names. This method
     # uses the +pluralize+ method on the last word in the string.

activesupport/test/inflector_test.rb

@@ -98,6 +98,12 @@ def test_tableize
     end
   end
 
+  def test_parameterize
+    StringToParameterized.each do |some_string, parameterized_string|
+      assert_equal(parameterized_string, ActiveSupport::Inflector.parameterize(some_string))
+    end
+  end
+
   def test_classify
     ClassNameToTableName.each do |class_name, table_name|
       assert_equal(class_name, ActiveSupport::Inflector.classify(table_name))

activesupport/test/inflector_test_cases.rb

@@ -142,6 +142,11 @@ module InflectorTestCases
     "NodeChild"        => "node_children"
   }
 
+  StringToParameterized = {
+    "Donald E. Knuth"                     => "donald-e-knuth",
+    "Random text with *(bad)* characters" => "random-text-with-bad-characters"
+  }
+
   UnderscoreToHuman = {
     "employee_salary" => "Employee salary",
     "employee_id"     => "Employee",